package org.dromara.common.mybatis.core.page;

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.ObjectUtil;
import cn.hutool.db.sql.Order;
import com.baomidou.mybatisplus.core.metadata.OrderItem;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.google.common.base.CaseFormat;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.NoArgsConstructor;
import org.dromara.common.core.exception.ServiceException;
import org.dromara.common.core.utils.StringUtils;
import org.dromara.common.core.utils.sql.SqlUtil;
import lombok.Data;

import java.io.Serial;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 分页查询实体类
 *
 * @author fly
 */

@Builder
@AllArgsConstructor
@NoArgsConstructor
@Data
public class PageQuery implements Serializable {

    @Serial
    private static final long serialVersionUID = 1L;

    /**
     * 分页大小
     */
    private Integer pageSize;

    /**
     * 当前页数
     */
    private Integer pageNum;

    /**
     * 排序列
     */
    private String orderByColumn;

    /**
     * 排序的方向desc或者asc
     */
    private String isAsc;

    /**
     * 当前记录起始索引 默认值
     */
    public static final int DEFAULT_PAGE_NUM = 1;

    /**
     * 每页显示记录数 默认值 默认查全部
     */
    public static final int DEFAULT_PAGE_SIZE = Integer.MAX_VALUE;

    public <T> Page<T> build() {
        Integer pageNum = ObjectUtil.defaultIfNull(getPageNum(), DEFAULT_PAGE_NUM);
        Integer pageSize = ObjectUtil.defaultIfNull(getPageSize(), DEFAULT_PAGE_SIZE);
        if (pageNum <= 0) {
            pageNum = DEFAULT_PAGE_NUM;
        }
        Page<T> page = new Page<>(pageNum, pageSize);
        List<OrderItem> orderItems = buildOrderItem();
        if (CollUtil.isNotEmpty(orderItems)) {
            page.addOrder(orderItems);
        }
        return page;
    }

    /**
     * 顺序 - 升序
     */
    public static final String ORDER_ASC = "ASC";

    /**
     * 顺序 - 降序
     */
    public static final String ORDER_DESC = "DESC";

    /**
     * 字段
     */
    private String sort;

    /**
     * 顺序
     */
    private String by;

    public void setSort(String sort) {
        if (sort != null) {
            this.sort = CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, sort);
        }
    }

    public void setBy(String by) {
        if (by != null) {
            this.by = by.toUpperCase();
        }
    }


    private List<Order> sorts;

    @Data
    public static class Order {
        /**
         * 字段
         */
        private String sort;

        /**
         * 顺序
         */
        private String by;

        public Order(String sort, String by) {
            this.sort = CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, sort);
            this.by = by.toUpperCase();
        }

        public void setSort(String sort) {
            if (sort != null) {
                this.sort = CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, sort);
            }
        }

        public void setBy(String by) {
            if (by != null) {
                this.by = by.toUpperCase();
            }
        }

        public Order() {
        }
    }

    /**
     * 构建排序
     * <p>
     * 支持的用法如下:
     * {isAsc:"asc",orderByColumn:"id"} order by id asc
     * {isAsc:"asc",orderByColumn:"id,createTime"} order by id asc,create_time asc
     * {isAsc:"desc",orderByColumn:"id,createTime"} order by id desc,create_time desc
     * {isAsc:"asc,desc",orderByColumn:"id,createTime"} order by id asc,create_time desc
     */
    private List<OrderItem> buildOrderItem() {
        if (StringUtils.isBlank(orderByColumn) || StringUtils.isBlank(isAsc)) {
            return null;
        }
        String orderBy = SqlUtil.escapeOrderBySql(orderByColumn);
        orderBy = StringUtils.toUnderScoreCase(orderBy);

        // 兼容前端排序类型
        isAsc = StringUtils.replaceEach(isAsc, new String[]{"ascending", "descending"}, new String[]{"asc", "desc"});

        String[] orderByArr = orderBy.split(StringUtils.SEPARATOR);
        String[] isAscArr = isAsc.split(StringUtils.SEPARATOR);
        if (isAscArr.length != 1 && isAscArr.length != orderByArr.length) {
            throw new ServiceException("排序参数有误");
        }

        List<OrderItem> list = new ArrayList<>();
        // 每个字段各自排序
        for (int i = 0; i < orderByArr.length; i++) {
            String orderByStr = orderByArr[i];
            String isAscStr = isAscArr.length == 1 ? isAscArr[0] : isAscArr[i];
            if ("asc".equals(isAscStr)) {
                list.add(OrderItem.asc(orderByStr));
            } else if ("desc".equals(isAscStr)) {
                list.add(OrderItem.desc(orderByStr));
            } else {
                throw new ServiceException("排序参数有误");
            }
        }

        if (!CollUtil.isEmpty(getSorts())) {
            getSorts().stream().iterator().forEachRemaining(order -> list.add(ORDER_ASC.equals(order.getBy()) ? OrderItem.asc(order.getSort()) : OrderItem.desc(order.getSort())));
        } else if (!StringUtils.isEmpty(getBy())
            && !StringUtils.isEmpty(getSort())) {
            list.add(ORDER_ASC.equals(getBy()) ? OrderItem.asc(getSort()) : OrderItem.desc(getSort()));
        }

        return list;
    }


}
